听第9段材料，回答第13~16题。第13题：

A.Certificate of Inspection

B.American Bureau of Shipping code

C.Muster List ("Station Bill")

D.Safety of Life at Sea Convention

A.Certificate of Inspection

B.American Bureau of Shipping code

C.Minerals Management Service regulations

D.Safety of Life at Sea Convention

A、Ordinary seamen conduct repair work.

B、Ordinary seamen paint the superstructure above the main deck.

C、Ordinary seamen take regular courses on board a ship.

D、Ordinary seamen take the tasks such as buffing, scaling, and cleaning the deck.

A.Master of the vessel

B.USCG Officer in Charge of Marine Inspection

C.Owner or operator of the vessel

D.Company's personnel director

A．about half the number on board

B．about one third of the number on board

C．all the number on board

D．about two thirds of the number on board

A.One approved flotation cushion for each person on board

B.One approved life preserver for each person on board and one life ring

C.One approved inflatable vest for each person on board

D.Lifeboat capacity equal to 1 1/2 times the number of persons on board

How many adult life jackets are required on board a ship ________．

A.Enough for 100 percent of the persons allowed on board

B.One for each work station and industrial work site

C.Enough for 150 percent of the persons allowed on board

D.Both A & B above